Abstract The transformation of exponentially decaying waveform (the time dependence of detection probability) of a Mössbauer γ -ray photon into a regular sequence of short nearly bandwidth-limited pulses in a vibrating recoilless resonant absorber is studied. The case of dual-tone vibration at the fundamental frequency and its second harmonic under experimentally feasible conditions is considered. We show that this technique allows one to shorten pulses and increase the ratio of pulse separation to pulse length as well as to enlarge pulse amplitude compared to the pulses produced in harmonically vibrating absorber. The obtained results pave the way to the development of the time-resolved Mössbauer γ -ray spectroscopy and manipulation of quantum information in hard x-ray/ γ -ray range.
Abstract The transformation of exponentially decaying waveform (the time dependence of detection probability) of a Mössbauer γ -ray photon into a regular sequence of short nearly bandwidth-limited pulses in a vibrating recoilless resonant absorber is studied. The case of dual-tone vibration at the fundamental frequency and its second harmonic under experimentally feasible conditions is considered. We show that this technique allows one to shorten pulses and increase the ratio of pulse separation to pulse length as well as to enlarge pulse amplitude compared to the pulses produced in harmonically vibrating absorber. The obtained results pave the way to the development of the time-resolved Mössbauer γ -ray spectroscopy and manipulation of quantum information in hard x-ray/ γ -ray range.
Recently, an exponentially decaying waveform (the time dependence of detection probability) of a M\"ossbauer \ensuremath{\gamma}-ray photon was transformed into a regular sequence of short pulses in a sinusoidally vibrating recoilless resonant absorber [F. Vagizov, V. Antonov, Y. V. Radeonychev, R. N. Shakhmuratov, and O. Kocharovskaya, Coherent control of the waveforms of recoilless \ensuremath{\gamma}-photons, Nature (London) 508, 80 (2014)]. In the present paper, we show that the peak amplitude of the pulses can be considerably increased via joint adjustment of optical depth of the absorber and the initial phase of its vibration. This is due to reduction of the photoelectric absorption and maximizing the constructive temporal interference of spectral content of the single-photon wave packet in an optically deep absorber. The ultimate capabilities for transforming a waveform of a 14.4-keV photon from a 57Co radioactive source into a regular train of pulses in a harmonically vibrating 57Fe recoilless resonant absorber are discussed. We show that the shortest pulse duration, produced by this technique, is limited by the highest available vibration frequency of a piezoelectric transducer and at present can be as short as 7.7 ps. The maximum achievable detection probability of the transformed photon at the experimentally feasible conditions is more than two times higher than peak detection probability of the photon emitted by the source and nearly 5.5 times higher than obtained in the above reference.
A technique to transform the waveform of a 14.4 keV photon (time dependence of the photon detection probability or, equivalently, the intensity of the single-photon wave packet) into a regular sequence of short, nearly bandwidth-limited pulses with a controlled number of pulses is proposed. It is based on coherent forward scattering of single X-ray photons from a synchrotron Mössbauer source (SMS) in an optically thick, vibrating, recoilless 57Fe resonant absorber. The possibility of compressing the waveform of an SMS photon into a single short bell-shaped pulse is predicted. The experiment is proposed for compressing a 100 ns duration 14.4 keV single-photon wave packet produced by SMS at the European Synchrotron Radiation Facility (ESRF) into a single bell-shaped pulse of less than 20 ns duration and more than twice the peak intensity. Such single-photon coherent pulses are promising for applications in the fast-developing field of X-ray quantum optics, including possible implementation of quantum memory.
We report a method for coherent control of γ-photons, enabling the shaping of γ-ray intensity in nearly arbitrary waveforms. Different intensity waveforms are created by adjusting the motion profile of a resonant absorber (an ensemble of Mössbauer nuclei) and tuning the energy of the incident radiation. A crucial aspect of this method is the use of a low fundamental frequency of vibrations, which broadens the possibilities for γ-ray control. The results of numerical simulations are experimentally validated by generating single and double γ-pulses and inducing short-term absorption. For this, a resonant absorber containing 57Fe nuclei was vibrated with different motion profiles composed of 12 harmonics with a fundamental frequency of 1 MHz. The proposed technique represents an advancement in the manipulation of γ-rays, and potentially x rays, paving the way for the performance of unique types of γ-ray or x-ray quantum experiments and the development of tools such as adjustable table-top γ-pulse sources or γ-ray or x-ray delays and gates. Moreover, inverse application of the method enables investigation of motion at the picometer scale.
We study propagation of $\ensuremath{\gamma}$ radiation from a M\"ossbauer radioactive source through a vibrating recoilless resonant absorber and find the optimal conditions to produce a periodic train of $\ensuremath{\gamma}$-ray pulses with maximum peak intensity, several times higher than the intensity from the source, and minimum duration, much shorter than the lifetime of the emitting nuclear state of the source. The shape, duration, and repetition rate of the pulses are tunable in a wide range. We propose modifications of the recently reported experiment [F. Vagizov et al., Nature (London) 508, 80 (2014)] to produce pulses with higher peak intensity and shorter duration using absorbers enriched by the resonant nuclei and discuss possible applications of the generated pulses for the time-domain M\"ossbauer spectroscopy.
We propose a technique for transforming the intensity of quasi-monochromatic recoilless radiation with a photon energy of 93.3 keV, emitted by radioactive Mössbauer sources 67Ga or 67Cu, into a sequence of short pulses with individually and independently controlled, on demand, the moments of appearance of pulses, as well as the peak intensity, duration and shape of each pulse. The technique is based on the transmission of recoilless (Mössbauer) 93.3-keV photons from the source through a medium containing resonantly absorbing 67Zn nuclei. The pulses are formed due to the rapid reciprocating movement of the source relative to the absorber at specified moments in time along the direction of photon propagation at a distance not exceeding half the radiation wavelength. The produced sequences of γ -ray pulses are similar to the digitization of information carried by electromagnetic waves. They can also be used to develop Mösbauer spectroscopy of the atomic and subatomic structures, as well as open novel opportunities for γ -ray quantum optics.
We propose a technique that makes it possible to transform the intensity of a quasi-monochromatic single-photon wave packet, emitted by a radioactive Mössbauer gamma-ray source, into a sequence of short bursts with an arbitrary number of bursts, including a single burst. In addition, the technique allows one to individually and independently control, on demand, the moments of the burst appearance, as well as the peak intensity, duration and shape of each burst in the sequence. The technique is based on the transmission of Mössbauer (recoilless) photons through a resonantly absorbing medium, which is rapidly displaced at some moments of time relative to the source (or vice versa) along the photon propagation direction at a distance less than the photon wavelength, and returned to its original position. The burst durations can be comparable to the duration of the single-photon pulses produced by synchrotrons but have the controlled spectral-temporal characteristics. We show that the proposed technique can be implemented on the basis of currently available equipment with use of 14.4-keV recoilless photons, emitted by Co-57 source, and Fe-57 absorber, which opens up prospects for its applications in Mössbauer spectroscopy and x-ray quantum optics.